C# WinForm中Panel实现用鼠标操作滚动条的实例方法

方法如下：
在窗体的load事件注册滚动事件，并增加对应的方法

private void formsample_load(object sender, eventargs e)
        {

            //注册事件
            this.mousewheel += new mouseeventhandler(formsample_mousewheel);
        }

        /// <summary>
        /// 滚动方法
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        void formsample_mousewheel(object sender, mouseeventargs e)
        {
            //获取光标位置
            point mousepoint = new point(e.x,e.y);
            //换算成相对本窗体的位置
            mousepoint.offset(this.location.x, this.location.y);      
            //判断是否在panel内
            if (pnldownload.rectangletoscreen(
              pnldownload.displayrectangle).contains(mousepoint))
            {
                //滚动
                pnldownload.autoscrollposition = new point(
, pnldownload.verticalscroll.value - e.delta);
            }
        }